The present invention concerns a mechanism for a disc brake according to the preamble of claim 1. The function of the brake mechanism is to transfer the braking movement and to amplify the force from a braking cylinder to a disc brake pad and to adjust the running clearance between brake pad and disc. The disc brake mechanism is to be placed in a disc brake caliper and consists of a thrust yoke, a cross bar, an adjuster means and a lever. The thrust yoke is connected to a brake pad holder provided with a brake pad for braking engagement with a brake disc, and the thrust yoke is axially movable in the caliper. The function of the lever is to transmit a braking force from a brake cylinder, attached to the caliper, to the cross bar. From the cross bar the braking force is transmitted to the thrust yoke.
A brake mechanism of this kind is primarily intended for a disc brake for a road vehicle but may be used for rail vehicles as well. The brake mechanism of the invention is developed for all kinds of heavy vehicles.
Today it is common to use either one or two thrust plates acting on the brake pad. The use of one thrust plate means reduced costs and less required space. Two thrust plates are used to get a better distribution of the forces acting on the brake pad. By having two thrust plates the risk of skewing and uneven wear is reduced. In the present invention the low costs of a single thrust plate is combined with the stability of two thrust plates.
One object of the present invention is to provide a mechanism having fewer parts giving reduced weight and lower costs. The mechanism must yet be powerful enough to withstand the expected strains and stresses.
A further object of the present invention is to hold the disc brake mechanism together as a unit in order to facilitate handling and assembly in the disc brake caliper.
Still a further object is that forces acting on the brake pad should be evenly distributed in order to avoid uneven wear of the brake pad.
The above objects are fulfilled by a brake mechanism according to the characterizing part of claim 1.